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Notes: Abstract The criteria required for an effective screening strategy for osteoporosis are largely met in Caucasian women. The disease is common and readily diagnosed by the measurement of bone mineral with single- or dual-energy absorptiometry. Such measurements have high specificity but lower sensitivity, so that the value of the technique is greater for those identified as being at higher risk. Against this background there is little evidence that osteoporosis can usefully be tackled by a public health policy to influence risk factors such as smoking, exercise and nutrition. This suggests that it is appropriate to consider targetting of treatment with agents affecting bone metabolism to susceptible individuals. Since the main benefits of the use of hormone replacement therapy (HRT) are probably on cardiovascular morbidity, the major role for selective screening is to direct non-HRT interventions. An appropriate time to consider screening and intervention is at the menopause, but screening at later ages is also worthy of consideration. Since the cost of screening is low and that of bone-active drugs is high, the selective use of screening techniques will improve the cost-benefit ratio of intervention.

Notes: Abstract The aims of this study were to determine (1) whether acute suppression of bone formation could be evaluated after the administration of corticosteroids in man by quantitative bone histomorphometry; and (2) whether there were significant differences between the effects of prednisone and its analog deflazacort. Thirteen patients who needed high-dose corticosteroid therapy were randomly allocated to two groups of treatment (prednisone or deflazacort). Quantitative bone histomorphometry, using the technique of triple labeling, and biochemical measurements of bone turnover were studied. There were no differences in biochemical indices of bone turnover between prednisone and deflazacort at the beginning and end of the 15 days of treatment course. During corticosteroid treatment, there were no significant changes in biochemical indices of bone turnover but a significant decline in total alkaline phosphatase (P〈0.01). Histomorphometric indices, as revealed by measurements of tetracycline interval and extent of labeling, showed no significant differences in either mineral apposition rate or bone formation rate in the two groups. We conclude that the acute glucocorticoid suppression of bone turnover by glucocorticoids is not detectable within the first 2 weeks of treatment by histomorphometric techniques. No differences in bone effects of prednisone and deflazacort were detected in this short-term study.

Notes: Abstract. Densitometric measurements are prone to imprecision in elderly subjects and the present study was primarily designed to dissect out the effects of age and bone mineral density on proximal femur dual energy x-ray absorptiometry (DXA) reproducibility. The study comprised 17 elderly women (mean age 74.6 years, range 65–84 years), 13 early postmenopausal women with osteopenia (mean age 56.2 years, range 50-63 years), and 17 elderly men (mean age 73.8 years, range 65-86 years). Each subject was given triplicate proximal femur scans by a QDR 2000 Densitometer (Hologic Inc., Waltham, MA) with repositioning between scans. Because of subject selection in the early postmenopausal women there were no significant differences in bone mineral density (BMD) at any site among the three groups. Despite this, reproducibility errors expressed as either coefficient of variation (CV) % or mean standard deviation (SD) were greater in the elderly subjects, regardless of gender, when compared with the younger female subjects. The variability in measurement errors with age were least marked for the total hip and trochanteric sites. Within the elderly subjects, BMD appeared to exert little influence on measurement errors. We conclude that short-term proximal femur reproducibility is dependent on age-related factors other than BMD. There is no influence of gender on the measurement errors. It is likely that local factors (e.g., hip osteoarthritis) or general frailty may influence repositioning but this needs further exploration. In the meantime, the total hip and trochanteric sites should be used as they provide the most reproducible measurements in the elderly.

Notes: Abstract.

Notes: Abstract In a prospective study of201Tl-99mTc subtraction scintigraphy, 61 hyperparathyroid patients were investigated prior to neck exploration. At surgery, 46 adenomatous and 28 hyperplastic parathyroid glands were excised. We examined the relationship between the pathological category of these glands, their mass, uptake of201Tl thallous chloride, and the frequency of true-positive and false-negative scintigraphic findings. The variation of sensitivity with parathyroid mass was found to be similar for both adenomatous and hyperplastic glands, with a detection threshold that lay in the range 0.3–0.8 g. The higher overall sensitivity for the detection of adenomas (85%) compared with hyperplasias (44%) was due to the smaller mean weight of the latter. When the parathyroid uptake of thallium was quantified scintigraphically, the practical detection limit of subtraction scanning was found to be an uptake of 0.015%. For glands greater than 1.5 g in weight, uptake increased linearly with mass, and specific uptakes were within the range 0.01–0.04%/g. Below lg, certain small glands had much higher specific uptakes, up to 0.2%/g. The range of specific uptakes found was similar for both adenomatous and hyperplastic categories. Multinodular or diffuse goitre was a cause of failure in 10% of investigations. In a further 5%, a solitary thyroid nodule gave rise to a false-positive result.

Notes: Abstract: Vertebral fractures may be minor or lead to pain, decreased physical function, immobility, social isolation and depression, which together contribute to quality of life. A Working Party of the European Foundation for Osteoporosis has developed a specfic questionnaire for patients with vertebral fractures. This questionnaire, QUALEFFO, includes questions in the domains pain, physical function, social function, general health perception and mental function. QUALEFFO was validated in a multicenter study in seven countries. The study was done in 159 patients aged 55–80 years with clinical osteoporosis, i.e., back pain and other complaints with at least one vertebral fracture and lumbar bone mineral density T-score 〈−1. Patients with a recent vertebral fracture were excluded because of unstable disease. Controls were age- and sex-matched, and did not have chronic back pain or vertebral fractures. Subjects with conditions exerting a major influence on quality of life were excluded. The QUALEFFO was administered twice within 4 weeks and compared with a generic questionnaire, the Short Form 36 of the Medical Outcomes Study (SF-36). Standard spinal radiographs were made for assessment of vertebral height. Seven questions were removed from the analysis because of low response rate, linguistic ambiguities or redundancy. The 41 remaining questions were analyzed for repeatability, internal consistency and the capacity to discriminate between patients with vertebral fractures and controls. Comparison with the SF-36 was performed within similar domains by conditional logistic regression and by receiver operating characteristic (ROC) curves. The repeatability of QUALEFFO was good (kappa statistics 0.54–0.90) and 26 of 41 questions had a kappa score ≥0.70. The internal consistency of the five domains was adequate, with Crohnbach α around 0.80. All except five questions discriminated significantly between patients and controls. The median scores of QUALEFFO were significantly higher in patients with vertebral fractures than in controls in all five domain (p〈0.001), which is consistent with decreased quality of life in patients with osteoporosis. Spinal radiographs were assessed using the McCloskey–Kanis algorithm. According to this, 124 patients (78%) had vertebral fractures of ≥3 SD severity, in contrast with 7 controls (4%). Significant correlations existed between scores of similar domains of QUALEFFO and the SF-36, especially for pain, physical function and mental function. All five domains within each questionnaire discriminated significantly between fracture cases and controls. The odds ratios for pain and social function were greater for QUALEFFO, while general health perception was more discriminating using the SF-36. The ROC curve analysis of QUALEFFO indicated that all five domains were significantly predictive of vertebral fractures. When comparing similar domains of the two questionnaires, QUALEFFO domains demonstrated significantly better performance for pain, physical function and social function. The QUALEFFO total score and SF-36 physical composite score showed similar performance. In conclusion, QUALEFFO is repeatable, coherent and discriminates well between patients with vertebral fractures and control subjects. The results of this study confirm the decreased quality of life in patients with vertebral fractures.

Notes: Abstract The role of vitamin D in the prevention of hip fracture is controversial and protective effects appear to be confined to the institutionalized and elderly population. The aim of this study was to assess the interaction of age and body mass index (BMI) on the effects of vitamin D on the risk of hip fracture in the community. We studied 1634 women with low-energy fractures of the hip aged 50 years or older, and 3532 age-matched controls from 14 centres in six Mediterranean countries (the MEDOS study), with a structured retrospective questionnaire. The use of vitamin D supplements was associated with a modest and non-significant decrease in the risk of hip fracture (RR=0.74; 95% confidence interval (CI) 0.53–1.03;p=0.07). The risk reduction was influenced by age and body mass. Women aged above 80 years had a significant decrease in the relative risk of hip fracture (RR=0.63; 95% CI 0.40–0.98) as did women with a BMI below 20 kg/m2 (RR=0.45; 95% CI 0.24–0.84). Elderly women were more likely to have a low BMI but the elderly did not appear to benefit from vitamin D where their BMI was 20 kg/m2 or higher. The findings could not be explained by differences in sun exposure or in physical exercise. We conclude that the use of vitamin D for the prevention of hip fracture might usefully be targeted to the frail and elderly.

Notes: Abstract We assessed a method for the measurement of ultrasound velocity in cortical bone of the human tibia using a probe designed to minimize the effects of surrounding soft tissues. Of four different measurement values, the maximum velocity (average of the five highest readings) gave the lowest errors of reproducibility in relation to the population variance (standardized coefficient of variation=1.8%). The maximum velocity varied according to the tibial site measured and for practical reasons the mid-tibial site was chosen for further study. The short-term intra- and inter-observer reproducibilities (coefficients of variation) were 0.35% (n=22) and 0.50% (n=27) respectively. Long-term reproducibility over 4 months in 31 subjects was 0.68%. There was no significant difference in maximum ultrasound velocity between the dominant and non-dominant tibia in 78 women (3764±209 vs 3763±199 m/s). Tibial ultrasound velocity was significantly higher in 73 premenopausal women (3999±102 m/s) than in 129 women referred for assessment of postmenopausal osteoporosis (3780±168 m/s), 26 women with steroid-induced osteoporosis (3790±188 m/s) and 4 women with hyperparathyroidism (3575±261 m/s). In premenopausal women, ultrasound velocity did not correlate significantly with age, height, weight or body mass index. In women with postmenopausal osteoporosis, ultrasound velocity decreased with age after the menopause (r=−0.47,p〈0.0001) and body weight exerted a weaker protective effect. The apparent annual decrease in velocity with age in postmenopausal osteoporosis (8.5 m/s) was comparable to the error of reproducibility. We conclude that the technique for measuring tibial ultrasound velocity is highly reproducible in relation to the distribution of values in the population and is sensitive to age- and osteoporosis-induced changes in bone. Further studies are required to examine its relationship to other indices of skeletal status to determine the biological and clinical relevance of the technique.

Notes: Preamble Significant developments have occurred in the field of osteoporosis over the past several years. There is now considerable information concerning its impact on general health and an international consensus concerning the definition of osteoporosis. Conceptually, this recognizes the multifactorial nature of the events which give rise to the fractures, but operational definitions have now been agreed and have gained a wide measure of acceptance. Accurate and precise diagnostic tools are also available. Finally, there is substantial evidence that the natural history of osteoporosis can be modulated by agents which in turn decrease the risk of fracture. Despite an increasing professional and public awareness of osteoporosis, the management of osteoporosis has been confined mainly to specialists. With the large number of affected individuals and the wider availability of diagnostic aids and safe treatments, there is a need for osteoporosis to be managed predominantly by the primary care physician. Against this background the European Foundation for Osteoporosis and Bone Disease through their Scientific Advisory Board has recognized a need to develop practice guidelines for primary care physicians which are summarized in this paper.

Notes: Abstract: Bone mineral density measurements are widely used to estimate the relative risk of hip fracture. In addition, many other risk factors have been identified, some of which are known to add to the risk independently of other risk factors, including bone mineral density measurements. In this paper we develop an algorithm that converts relative risks for hip fracture to absolute (15 years and lifetime) risks, modeled on the population of Sweden. Lifetime risks increased as expected with increments in relative risk. Average lifetime risk in women at the age of 50 years was 22.7%, which increased to 64.9% when the relative risk was 6.0. In men the risk increased from 11.1% to 41.3%. The identification of high-risk groups had little effect on the specificity of assessments but increased the sensitivity over a wide range of assumptions. The increment in lifetime risk was relatively stable across all ages, reducing the complexity of computing lifetime risks from relative risk. The derivation of absolute risk from relative risk permits the optimization of selection of individuals or populations either for further risk assessment or for treatment.